Re: [RFC PATCH v2 1/9] vfio/pci: split vfio_pci_device into public and private parts

[Yan Zhao]

On Sat, Feb 08, 2020 at 03:48:31AM +0800, Alex Williamson wrote:
> On Thu, 30 Jan 2020 21:09:56 -0500
> Yan Zhao <yan.y.zhao@xxxxxxxxx> wrote:
> 
> > split vfio_pci_device into two parts:
> > (1) a public part,
> >     including pdev, num_region, irq_type which are accessible from
> >     outside of vfio.
> > (2) a private part,
> >     a pointer to vfio_pci_device_private, only accessible within vfio
> > 
> > Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
> > Signed-off-by: Yan Zhao <yan.y.zhao@xxxxxxxxx>
> > ---
> >  drivers/vfio/pci/vfio_pci.c         | 209 +++++++++++++++-------------
> >  drivers/vfio/pci/vfio_pci_config.c  | 157 +++++++++++----------
> >  drivers/vfio/pci/vfio_pci_igd.c     |  16 +--
> >  drivers/vfio/pci/vfio_pci_intrs.c   | 171 ++++++++++++-----------
> >  drivers/vfio/pci/vfio_pci_nvlink2.c |  16 +--
> >  drivers/vfio/pci/vfio_pci_private.h |   5 +-
> >  drivers/vfio/pci/vfio_pci_rdwr.c    |  36 ++---
> >  include/linux/vfio.h                |   7 +
> >  8 files changed, 321 insertions(+), 296 deletions(-)
> 
> I think the typical solution to something like this would be...
> 
> struct vfio_pci_device {
> 	...
> };
> 
> struct vfio_pci_device_private {
> 	struct vfio_pci_device vdev;
> 	...
> };
> 
> External code would be able to work with the vfio_pci_device and
> internal code would do a container_of() to get access to the private
> fields.  What's done here is pretty ugly and not very cache friendly.
> Thanks,
>
got it, it's much better!
will change it. Thanks!

Yan